Solvent channels and voids within protein crystals are widely used in classical protein crystallography for diffusion of biological ligands or heavy metals (to solve the phase problem). Heavy atom cluster soaks are particularly useful to solve the phase problem because they add many electrons. However, it is currently difficult to control the placement of biological or synthetic molecules in the solvent channels or voids within a protein crystal. This is exceedingly challenging due in part to the difficult and lengthy experiments necessary to elucidate the dynamic structure of proteins.
What is needed, therefore, are methods for controlling placement of molecules within the solvent channel or void spaces within a protein crystal.